Self-balancing vehicles for transportation of individuals are known in the art. As described in U.S. Pat. No. 6,302,230B1 and AT299826 (Kamen), such vehicles are typically equipped with two coaxial, individually driven wheels, spaced apart and with a platform between, onto which a rider of the vehicle may stand facing in an intended forward direction of motion. Gyroscopic and accelerometer sensors detect changes in orientation of the platform and feed information to a motor control system. The motor system is programmed to maintain platform orientation horizontal within a certain range by rotating the wheels in any direction, having the effect of aligning the centers-of-gravity of the vehicle and the rider whilst the vehicle has a constant velocity. On some types, there is an upright handlebar connected to the platform, giving the rider ability to further control the vehicle by leaning sideways, whereby the wheels will rotate at different speeds and/or direction, causing the vehicle to turn.
Another variant of the above-described self-balancing vehicle is taught by U.S. Pat. No. 8,738,278B2 (Chen) in which a vehicle has two spaced, individually powered wheels that are controlled by a motor control system, with a platform between which is split laterally in two halves. Each half of the platform is associated with one wheel and its motor control system, and corresponds to the position of left and right feet of a rider of the vehicle. The two halves are pivotally coupled to one another, whereby the rider can control the relative speed and rotation direction of the two wheels independently using their feet to tilt the two platform sections. One benefit of this type of self-balancing vehicle is the lack of need for an upright handlebar, making the unit smaller and maneuverable without using the hands.
A third type of self-balancing vehicle disclosed by US20110220427A1 (Chen) a single large wheel and footrests on either side of the wheel. Friction pads extending upwards from each footrest are designed to give the rider more stability and comfort by providing support to the inside of the rider's calves.
A fourth type of self-balancing vehicle has a single wheel and a platform shaped like that of a skateboard. The rider places one foot on each side of a centrally positioned single wheel, and the intended direction of travel is sideways relative to the orientation of the rider. U.S. Pat. No. 9,101,817 Doerksen describes such a vehicle. There are also developments described in the art towards the safety aspects of this type of vehicle. Although the nature of an electric DC motor is that it can also be used in reverse as a brake, whereby the motor is used as a dynamo and electric energy is generated, more braking power may be desired. CN103191558A (Chu) describes a similar self-balancing board with a separate brake mechanism acting on the single central wheel, thereby increasing the braking power. U.S. Pat. No. 7,811,217 (Odien) discloses a self-balancing board with dual centrally positioned wheels, each having a brake associated with it. U.S. Pat. No. 7,424,927B2 (Hiramatsu) also describes a self-balancing board with a single central wheel, having auxiliary wheels in front and back. The auxiliary wheels are used to sense board angle via contact with a surface, each auxiliary wheel having sensors to determine the time the board has spent in a certain max tilt angle and feed information to the motor controller in order to initiate a controlled deceleration of the motor, and thus the central wheel.